Objective: The aim of this study was to explore the effect of low dose radiation on cytokine excreted by mice inbreathing of atomization of PYM Methods: Kunming male mice were randomly divided into three groups: blank group, PYM group (P group), low dose radiation+PYM group (P+L group).Mice of P+L group were given whole body low dose radiation 75 mGY, dose rate were 12.5 mGY/min. After 6 h, mice in both P+L group and P group were given inbreathe of atomization of PYM, concentration was 2 mg/mL. Mice were sacrificed after the dl, d7, d14, d21 and d28, IL-6 were detected in alveolar irrigating solution. The tissue samples of mice lung were fixed in 10% formalin, TNF-α and TGF-β were analyzed by immunohistochemistry. Results: Compared with P group, IL-6 in low dose radiation+PYM group were lower,near to blank group, the difference had notable statistical significance on the dl and the d7, while on the d14,d21,d28,the difference had not statisti-cal significance. It suggested that low dose radiation could reduce the resection of IL-6 at the begin of lung injure induced by low dose radiation.The expression of TGF-β and TNF-a in P+L group were lower than that in P group, but the difference in the two groups had statistical significance by gray analysis P＜0.05. Conclusion: In the early stage of lung injure caused by PYM in mice,low dose radiation of 75 mGY can reduce the secretion of IL-6,decrease the production of TGF-β and TNF-α.